Consider two 1.00 L buffer solutions at 25 °C based on the same monoprotic acid HA (pKa = 4.80):
• Buffer G: 0.30 M HA and 0.30 M NaA
• Buffer H: 0.30 M HA and 0.50 M NaA
For each buffer, calculate the minimum number of moles of HCl required to lower the pH by 1.00 unit, then state the difference H – G (in moles) between those two amounts.